Resistance of soybean lines infected with Blackeye cowpea mosaic virus under controlled conditions

Abstract

Ten soybean lines were investigated under screenhouse conditions for resistance to Blackeye cowpea mosaic virus (BlCMV) disease. The virus was detected and confirmed using Antigen Coated Plate-Enzyme Linked Immunosorbent Assay (ACP-ELISA). Each genotype was tested as inoculated and healthy control using completely randomized design replicated five times. Seedlings were infected with the virus by sap inoculation at 10 days after sowing. Disease incidence, disease severity, plant yield and yield components were recorded. Data were subjected to Analysis of Variance (ANOVA) at p<0.05 probability level. In most of the soybean lines, uninoculated plants gave significantly higher values of the growth and yield parameters. One hundred percent infection was found in the virus inoculated plants at 2 weeks post inoculation (WPI). The soybean line TGX 1990 – 46F was the most tolerant, as it exhibited moderate level of infection (symptom score = 3.0) at 5 WPI, and the lowest seed weight reduction (12.8 %). Genetic improvement of the high-yielding soybean genotypes against BlCMV infection would contribute significantly to sustainable yield and food security. The genotype TGX 1990 – 46F is therefore, recommended for breeding BlCMV-resistant soybean cultivars.